FUNCTION: [Summary is not available for the mouse gene. This summary is for the human ortholog.] The protein encoded by this gene is similar to the protein transgelin, which is one of the earliest markers of differentiated smooth muscle. The specific function of this protein has not yet been determined, although it is thought to be a tumor suppressor. Multiple transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Mar 2013] PHENOTYPE: Mice homozygous for a null allele display abnormalities in T cell physiology including cytotoxicity. [provided by MGI curators]